Charles e



[No Model.)

G. E. SCRIBNER.

SAFETY GUT-OUT.

No. 433,045. Patented July 29, 1890.

R O T E V N I ATTORNEY WITNESSES UNITED STATES- PATENT OFFICE.

CHARLES E. SCRIBNER, OF CHICAGO, ILLINOIS, ASSIGNOR TO THE WESTERN ELECTRIC COMPANY, OF SAME PLACE.

SAFETY CUT-OUT.

SPECIFICATION forming part of Letters Patent No. 433,045, dated July 29, 1890.

Serial No. 12 9,6 6 7. (No model.)

To all whom it may concern.-

Be it known that I, CHARLES E. SCRIBNER, a citizen of the United States, residing at Ohicago, in the county of Cook and State of Illinois, have invented a certain new and useful Improvement inLightning-Arresters,of which the following is a full, clear, concise, and exact description, reference being bad to the accompanying drawings, forming a part of 10 this specification.

My invention relates to lightning-arresters; and it consists in the use of a fusible wire in connection with a circuit-closer and signal apparatus.

My invention is designed more especially for use in telephone exchanges to guard against fires which have heretofore been caused by the low-tension currents from dynamo-e1ectric machines used in electric lighting, occasioned by wires carrying such currents becoming crossed with telephone-lines.

Such currents will not spark across to the ground-plate of the ordinary lightning-arrester like atmospheric or frictional electricity, which is of high tension.

Heretofore fine wire, which is fusible like German silver, has been used in telephoneexchanges as a lightning-arrester; but in case of damage no device has been used for automatically indicating at the annunciator of the line that the circuit of the line has been opened at the fusible wire prior to my invention herein.

In Figure 1 of the drawings I have shown 5 a front View of the switch-board and thelightning-arresters of four telephone-lines. Fig. 2 is a sectional view of the switch-board and the board which supports the lightning-arresters, with a diagram showing the circuit of a telephone-line and the automatic signaling device. Fig. 3 shows a modification of my device.

The circuit of the telephone-line a, as shown in Fig. 2, may be traced to the line-strip b of the ordinary lightning-arrester, and thence to the hook c, and thence through the fine German silver wire (1 to circuit-closer e, and thence through the springjack and annunciator upon the switch-board and to ground. The fusible wire cl holds the spring e away from the contact-plate f. When, however, this wire is burned off bylightning or an electric-light current, the spring will be released, and its tension is such that it will close upon contactplate f. The circuit of the power-generator g will thus be closed through the annunciator it upon the switch-board, and this circuit will remain closed until the wire (1 is replaced and the spring 6 lifted from contact-plate f.

It should be observed that the circuit of the do power-generator While closed through the annunciator prevents the operator or switchman from replacing the shutter. There is thus a constant signal before him indicating the line which has been opened by fusing the lightning-arrester wire until the damage is repaired. I have shown the battery 6, which may be used instead of the power-generator. The wire d should be of such length that an arc may not be formed over it. I prefer to make these wires of German silver or other metal, which is readily fused and about five or six inches in length.

Any other form of circuit-closer maybe used in place of the spring e. A lever held by a retractile spring would work just as well. The wire (I may be attached to the spring or lever e in any suitable manner, preferablybyt-hreading it through an eye near the end of the said lever. A loop in the upper end of the wire may then be conveniently slipped over the hook, thus holding the spring or lever away from the contact of the signal-circuit.

In Fig. 3 I have shown a portion of the conductor below the fine wire heavy, so that when the connection is severed this enlarged or heavy portion will fall, as indicated by the dotted lines, thus making the break of such length that the arc cannot form between the terminals.

There are many other forms of device that would readily suggest themselves to one acquainted with electric devices, whereby the break may be made of such length as to pre vent the possibility of an arc. I prefer to use a spring or gravity, as hereinbefore described.

I claim- 1. In a telephone-line circuit, the combination, with a fusible wire and an annunciator included in said circuit, a switch or circuit closer connected with said line-circuit, said switch or circuit closer being held in open circuit by said fusible wire, a generator or battery connected withthe contact-point of saidgenerator, and a connection from the fusible wire to the line-circuit, whereby on fusing the wire the annunciator is automatically disconnected from the line and at the same time connected through the battery or generator. In witness whereof I hereunto subscribe my name this 23d day of April, A. D. 1884.

CHARLES E. SCRIBNER.

\Vitnesses:

O. O. SHEPHERD, S. R. BARTON. 

